Keywords: Brain Injuries, Traumatic - Brain Concussion - Epidemiology - Brazil
Palavras-chave: Lesões Encefálicas Traumáticas - Concussão Encefálica - Epidemiologia - Brasil
INTRODUCTION
Traumatic brain injury (TBI) is defined as an injury caused by external force to the
head that results in an anatomical lesion or functional impairment of cranial or encephalic
structures. TBI is the leading cause of morbidity and mortality in polytrauma patients
and is one of the main causes of death in individuals under 45 years of age[1 ],[2 ],[3 ]. TBI can have a variety of causes, from falls to car accidents.
Because of its medical and socioeconomic burden, TBI is a major public health problem
worldwide. In the United States, 2.8 million emergency department visits were due
to TBI and approximately 124,000 of the most severe cases develop long-term impairment[4 ],[5 ]. In a single North American state, the annual direct medical cost of TBI was estimated
at $95 million, or $1.67 million per 100,000 people[6 ]. Although lifetime costs for patients with TBI vary according to their demographic
characteristics, the costs in Canadian dollars (CAD) for nonfatal cases was estimated
at $2,318 for males and $2,200 for females[6 ]. In Europe, TBI accounted for 37% of all injury-related deaths and was estimated
to cost a total of €22,907 million in 2010[7 ],[8 ]. Limited demographic and socioeconomic information on TBI is available from developing
countries[9 ].
Although TBI is widespread in Brazil and seems to have an economic and social impact,
there are very few epidemiological studies [10 ],[11 ]. A previous study reported that 40% of deaths in patients aged 5 to 9 years in Brazil
are due to TBI and that for every patient who dies, there are at least another three
more patients with long-term sequelae[12 ]. In addition, the annual cost of hospitalizations due to TBI has been estimated
at approximately R$ 156,300,000 (US$ 70,960,000)[11 ]. Unfortunately, these estimates may not reflect the actual Brazilian reality, due
in part to a high rate of unreported cases associated with immediate death and the
absence of a nearby emergency unit[11 ],[13 ],[14 ]. Furthermore, reliable quantification of the impact caused by TBI is usually not
accurate because measurements are not standardized and data collection on the incidence
and outcome of brain injury is incomplete. Therefore, clinical-epidemiological studies
are urgently needed to systematically investigate TBI in Brazil.
The current study aimed to investigate sociodemographic and clinical characteristics
of patients admitted to João XXIII Hospital with TBI and to identify factors that
may influence TBI morbidity and mortality. Also, the epidemiological data available
on TBI in Brazil was systematically review.
METHODS
Original report
This was an observational study conducted at the Joao XXIII Hospital. This hospital
is the main trauma center in the Metropolitan region of Belo Horizonte, the third
largest metropolitan region in Brazil with more than five million inhabitants. The
study was approved by the Human Research Ethics Committee of the Federal University
of Minas Gerais (COEP-UFMG).
All records of patients admitted to the Emergency Department of the Joao XXIII Hospital
within one month (July 2016) were evaluated using a structured protocol to obtain
sociodemographic and clinical information. The sociodemographic data included: (i)
sex, (ii) ethnicity, (iii) marital status, (iv) place of residence (Belo Horizonte,
metropolitan area, rural area), and (v) educational level. Clinical variables included
TBI features (Glasgow Coma Scale Score [GCS], CT neuroimaging changes, hemodynamic
instability, and ventilatory support) and hospital outcome. The following premorbid
variables were also recorded: (i) clinical comorbidities (any medical conditions that
were either secondary to the TBI or that the patient already had on admission) and
(ii) alcohol or illicit drug use (assessed via medical record). The causes, severity,
and type of TBI were also recorded. Neuroimaging results were included when available.
Exclusion criteria included: (i) follow-up patients, (ii) non-TBI patients (evaluated
via the absence of a TBI diagnosis on record), (iii) burn victims, (iv) exogenous
intoxications, (v) venomous animal bites, (vi) trauma patients without TBI, and (vii)
patients admitted 24 hours after TBI.
Statistical analyses were conducted with Statistical Package for the Social Sciences (SPSS) software, version 17.0. Chi-squared analyses were performed to determine statistically
significant frequencies of specific events in subgroups. Binary logistic regression
using a backward elimination approach was performed to determine which variables were
significantly associated with a longer hospital stay, defined as more than 24 hours,
as opposed to patients discharged within 24 hours after hospital admission. At the
João XXIII Hospital, patients whose state of consciousness remained stable for 24
hours were discharged. The following variables were included in the initial model:
age, sex, GCS score (greater than or equal to 13 or less than 12), comorbidity (presence
or absence), neuroimaging changes in computed tomography, and alcohol and drug use.
Stepwise backward selection was performed automatically using the SPSS software, version
17.0 (SPSS Inc., Chicago, IL, USA), and exclusion testing was done with the likelihood
ratio based on the conditional parameter estimates. The goodness of fit of the logistic
regression model was assessed using the Hosmer-Lemeshow test and a Receiver Operating
Characteristic (ROC) curve.
Systematic review
A systematic search for TBI studies in Brazil was performed independently by two authors
(JLVMB and ASM) in the PubMED and Lilacs databases using the MeSH/DeCS descriptors
for *traumatic brain injury, *epidemiology, and *Brazil. The inclusion criteria were
as follows: (i) studies evaluating sociodemographic and clinical information on TBI
cases in Brazil, (ii) original articles, and (iii) articles in Portuguese, Spanish,
or English.
RESULTS
In July 2016, 6,184 patients were admitted to the hospital, with 490 individuals diagnosed
with TBI. These 490 individuals accounted for 7.92% of the total admissions during
the research period. Four hundred seventy-seven records had enough information to
determine clinical outcome by age, while 436 records contained all information required
by our research protocol (data not shown).
Male patients formed the majority of our sample (n=324, 66.1%). Most TBI occurred
in adults (n=259, 52.9%). The most common mechanism for TBI was an unspecified fall
(n=124, 25.3%), followed by a fall from one’s own height (n=118, 24.1%) ([Table 1 ]).
Table 1
Sociodemographic data of the 490 available traumatic brain injury records.
n
%
Sex
Male
324
66.1
Female
166
33.9
Origin
Belo Horizonte
341
69.9
Metropolitan region
107
21.8
Metropolitan region outskirts
4
0.8
Outside metropolitan region (but still within the state of Minas Gerais)
29
5.9
Different State
2
0.4
Not informed
7
1.4
Age
0-18 years
149
30.4
19-59 years
259
52.9
60 years or more
82
16.7
Race
Brown
336
68.6
White
114
23.3
Black
32
6.5
Not informed
8
1.6
Outcome
Death
15
3.1
Discharge<24h
367
74.9
Discharge >24h
95
19.4
Hospitalized
7
1.4
Not informed
6
1.2
TBI mechanism
Unspecified fall
124
25.3
Fall from own height
118
24.1
Fall from superior height
43
8.8
Aggression
61
12.4
Firearm
6
1.2
Hit or struck by a car
45
9.2
Traffic collision
66
13.5
Non-traffic-related collision
16
3.3
Repetitive TBI
4
0.8
Not informed
7
1.4
TBI: traumatic brain injury.
The consequences of TBI differed considerably between age ranges (p=0.031). Deaths
by age range were: (i) ≤18 years old, 1 death/112 individuals (0.89%), (ii) 19-59
years old, 7 deaths/245 individuals (2.9%), and (iii) ≥60 years old, 6 deaths/79 individuals,
(7.6%). For the latter analysis, we considered only the 436 records that contained
all the data required by our research protocol.
Patients with TBI were divided into three groups based on their GCS score on hospital
admission. Patients who had GSC scores of 13-15 on hospital admission were classified
as “mild TBI”. Patients with GSC scores of 9-12 and 3-8 were classified as “moderate
TBI” and “severe TBI”, respectively[11 ],[13 ]. Patients with mild TBI accounted for the majority of TBI-related admissions and
comprised 87.4% of the total number of TBI cases. Moderate and severe TBI cases accounted
for 5.5 and 7.1% of TBI cases, respectively.
Next, we analyzed the mechanisms involved in TBI. The mechanisms of TBI were differed
significantly between the different severity categories of TBI. Unspecified fall and
traffic accident were the most frequent mechanisms for mild and severe TBI, respectively
(data not shown).
Male patients were the most affected by TBI across severity levels (p=0.022). We also
analyzed the incidence of comorbidities, CT neuroimaging changes, hemodynamic instability,
ventilatory support, and death across TBI severity levels ([Table 2 ]). Severe TBI accounted for the majority of deaths (57.1%), whereas mild and moderate
TBI accounted for 21.4% each. These deaths were related to TBI or TBI-associated injuries.
Table 2
Clinical variables across different traumatic brain injury severities.
GCS Score
p-value
Mild (13 to 15)
Moderate (12 to 9)
Severe (8 to 3)
Sex
Male
240 (63%)
19 (20.1%)
5 (16.1%)
0.022
Female
141 (37%)
5 (79.2%)
26 (83.9%)
Use of drugs
12 (3.1%)
2 (8.7%)
1 (3.2%)
0.36
Alcohol
71 (18.6%)
9 (37.5%)
3 (9.7%)
0.029
Comorbidity
95 (25%)
6 (25%)
2 (6.5%)
0.065
CT neuroimaging findings
39 (11.7%)
13 (54.2%)
24 (77.4%)
<0.001
Hemodynamic instability
0 (0%)
2 (8.3%)
4 (13.8%)
<0.001
Ventilation Support
4 (1.1%)
6 (25%)
24 (80%)
<0.001
Outcome
Death
3 (0.8%)
3 (13.6%)
8 (29.6%)
<0.001
Discharge>24h
61 (16.3%)
12 (54.5%)
16 (59.3%)
Discharge<24h
311 (82.9%)
7 (31.8%)
3(11.1%)
GCS: Glasgow coma scale; TBI: traumatic brain injury; CT: computed tomography.
In multivariate analysis, CT neuroimaging changes, the presence of medical comorbidities,
and a GCS score of 12 or less remained as significant factors associated with longer
hospital stay (>24h). The results are presented in [Table 3 ]. The logistic regression model was significant [Hosmer-Lemeshow goodness of fit
test (step 5): chi-square=3.177; p=0.204] and predicted variability yielded an area
under the curve (AUC) of 0.819 in the ROC analysis ([Figure 1 ]).
Table 3
Logistic model analysis to predict hospital admission for more than 24 hours.
Predictive variable
B
SE
Wald
df
p-value
OR
95%CI for OR
Lower
Upper
CT neuroimaging changes
-2.909
0.378
59.220
1
0.000
0.055
0.026
0.114
Medical comorbidity
-0.703
0.347
4.115
1
0.043
0.495
0.251
0.977
GCS score
-1.838
0.491
13.998
1
0.000
0.159
0.061
0.417
CT: computed tomography; GCS: Glasgow coma scale; B: beta coefficient; SE: standard
error; df: degrees of freedom; OR: Odds Ratio ; 95%CI: 95% confidence interval.
Figure 1 ROC curve of the logistic regression model (AUC=0.819).
In our systematic review, we first identified 148 possible titles in the PubMED and
Lilacs databases. Four articles were duplicates, and 114 studies were excluded after
title/abstract screening. Of these 114 articles, we set aside one review for further
reference screening. Thirty articles were fully analyzed, and 10 of these either did
not meet our inclusion criteria or did not contain the required information. Two additional
articles were identified in the references of review studies. Also, five additional
articles were identified while reading the selected manuscripts, giving us a total
of 27 eligible articles ([Figure 2 ]).
Figure 2 Flowchart of study selection process.TBI: traumatic brain injury.
Most studies were conducted in cities in the state of São Paulo (n=6)[15 ],[16 ],[17 ],[18 ],[19 ],[20 ]. Three studies dealt exclusively with epidemiological data on patients who developed
specific sequelae as a result of TBI, including diffuse axonal injury, intracranial
hypertension, and hypoxic brain damage[15 ],[21 ],[22 ]. Two studies addressed epidemiological data on patients affected by specific TBI
mechanisms, such as falls from their own height and firearm bullets[19 ],[23 ]. In most studies, mild TBI was found to be the most prevalent type (n=10)[16 ],[17 ],[23 ]
-
[30 ]. Additionally, young men were most commonly affected in all studies[11 ],[15 ]
-
[40 ]. There was limited information on ethnicity, with only three studies providing this
information[11 ],[15 ],[35 ]. Traffic/vehicle accidents were the most common mechanism for TBI, followed by falls[15 ]
-
[17 ],[19 ],[21 ],[24 ]
-
[31 ],[33 ]
-
[40 ]. This information is presented in [Table 4 ].
Table 4
Sociodemographic characteristics of Brazilian epidemiological studies on traumatic
brain injury.
Reference
Location
Study design
TBI severity/type
Most Common TBI severity (if applicable)
Male
Female
Most afflicted age group
Most afflicted ethnicity
Death
Most common TBI mechanism
n
%
n
%
Melo et al., 2019[24 ]
Parnaíba, Piauí, Brazil
Retrospective and Descriptive
General
Mild, n=50 (42.7%)
94
80.3%
23
19.7%
Mean age: 33.17 years (SD±17.2)
Not informed
Not informed
Automobile accidents, n=96 (82.1%)
Marinho et al., 2017[31 ]
Natal, Rio Grande do Norte, Brazil
Cross-sectional
General
Moderate, n=228 (61.3%)
317
85.2%
55
14.8%
18-30 years old, n=209 (56.2%)
Not informed
Not informed
Automobile accidents, n=95 (25.6%)
De Almeida et al., 2016[11 ]
Not applicable
Cross-sectional
General
Not informed
97,552 (mean per year)
77.7% (mean per year)
28,017 (mean per year)
22.3 (mean per year)
20-29 years old, n=28,905.4 (mean per year)
Mixed race, n=3,142,782.4* (mean per year)
*Greater number of cases because data were missing
n=9,714 (7.7%)(mean per year)
Not informed
Vieira et al., 2016[15 ]
São Paulo, São Paulo, Brazil
Prospective Cohort Study
Severe TBI with diffuse axonal injury
Not applicable
70
89.7%
8
10.3%
18-28 years old, n=34 (43.6%)
White, n=51 (65.4%)
n=24 (30.8%)
Traffic accidents, n=65 (83.3%)
Tavares et al., 2014[32 ]
Distrito Federal, Brasília, Brazil
Cross-sectional
General
Severe, n=108 (55.7%)
161
82.99%
33
17.01%
21-40 years old, n=67 (34.5%)
Not informed
Not informed
Physical aggression, n=57 (29.4%)
De Souza et al., 2013[19 ]
São Paulo, São Paulo, Brazil
Cross-sectional
General TBI caused by firearm projectiles
Severe, n=68 (37.6%)
154
85%
27
15%
21-30 years old, (47%)
Not informed
Not informed
Not applicable
Santos et al., 2013[25 ]
Pelotas, Rio Grande do Sul, Brazil
Epidemiological, Descriptive, and Retrospective
General
Mild, n=202 (40.7%)
314
63.3%
182
36.7%
0-15 years old, n=220 (44.3%)
Not informed
n=2 (0.4%)
Falls, n=233 (47.0%)
Fernandes et al., 2013[33 ]
Not applicable
Cross-sectional, descriptive
General
Not informed
358,780
81.5%
81,706
18.5%
14-34 years old, n=231,827 (53.0%)
Not informed
n=52,087 (12.0%)
Falls, n=154,170 (35.0%)
Carvalho Viégas et al., 2013[34 ]
Ananindeua, Pará, Brazil
Epidemiological, Cross-sectional, observational
General
Not informed
220
88%
30
12%
20-30 years old, n=81 (32.4%)
Not informed
n=55 (22%)
Traffic accidents, n=91 (36.4%)
Ruy and Rosa, 2011[35 ]
Criciúma, Santa Catarina, Brazil
Cross-sectional, descriptive, retrospective
General
Severe, n=63 (67.7%)
82
88.2%
11
11.8%
Mean age: 34.6 years (SD±16.7)
White n=84 (90.3%)
n=25 (26.9%)
Automobile accidents, n=52 (55.9%)
Moura et al., 2011[26 ]
Petrolina, Pernambuco, Brazil
Cross-sectional, epidemiological
General
Mild, n=54 (53.47%)
87
86.14%
14
13.86%
21-40 years old, n=52 (51.49%)
Not informed
n=8 (7.92%)
Motorcycle accident, n=45 (44.55%)
Ramos et al., 2010[36 ]
Caruaru, Pernambuco, Brazil
Document-based
General
Not informed
139
81.2%
32
18.7%
25-49 years old, n=56 (29.9%)
Not informed
Not informed
Motorcycle accident, n=34 (19.9%)
Guerra et al., 2010[21 ]
Belo Horizonte, Minas Gerais, Brazil
Retrospective cohort study
General TBI patients who developed intracranial hypertension
Severe, n=132 (100%)
89
67.4%
43
32.6%
7-9 years old
Not informed
n=68 (51.5%)
Getting hit by a vehicle, n=68 (51.5%)
Martins et al., 2009[37 ]
Florianópolis, Santa Catarina, Brazil
Prospective
Severe
Not applicable
631
84%
117
15.6%
Mean age: 34.8 years old (SD±16.3)
Not informed
n=249 (33.3%)
Road accident, n=225 (30.1%)
Braga et al., 2008[23 ]
Florianópolis, Santa Catarina, Brazil
Prospective
General TBI caused by one’s own height
Mild, n=69 (90.7%)
44
57.9%
32
42.1%
Mean age for men: 44.7 years
Mean age for women: 47.2
Not informed
Not informed
Not applicable
Faria et al., 2008[38 ]
Uberlândia, Minas Gerais, Brazil
Epidemiological, Prospective
General (Severe and moderate were grouped together)
Severe and moderate (grouped together), n=56 (66.7%)
68
80.9%
16
19.1%
Mean age for severe and moderate: 40.6 years
Mean age for mild: 34.8
Not informed
Not informed
Transport accidents, n=54 (64.74%)
Pereira et al., 2006[27 ]
Aracaju, Sergipe, Brazil
Longitudinal Prospective
General
Mild, n=422 (89%)
344
73%
126
27%
10-29 years old
Not informed
n=3 (0.6%)
Accidental fall, n=148 (31.5%)
Melo et al., 2006[28 ]
Salvador, Bahia, Brazil
Cross-sectional descriptive
General
Mild, n=249 (63.8%)
280
71.8%
110
28.2%
Not applicable
(Study conducted on a specific group age (0-19 years old)
Not informed
Not informed
Fall from height, n=134 (34.4%)
Melo et al., 2004[29 ]
Salvador, Bahia, Brazil
Cross-sectional
General
Mild, n=146 (38.4%)
460
82.9%
95
17.1%
21-30 years old, n=128 (23.2%)
Not informed
n=127 (22.9%)
Traffic accidents, n=226 (40.7%)
Dantas Filho et al., 2004[39 ]
Campinas, São Paulo, Brazil
Cross-sectional
Severe
Not applicable
166
80.58%
40
19.42%
Mean age: 29.21 years old
Not informed
n=75 (36.40%)
Traffic accidents, n=147 (71.36%)
Gusmão et al., 2002[22 ]
Belo Horizonte, Minas Gerais, Brazil
Prospective
Fatal TBI victims
Not applicable
90
75.0%
30
25.0%
Mean age: 37.5 years old (SD±18.3)
Not informed
Not applicable (Post-mortem study)
Not applicable (all patients came from traffic accidents)
Koizumi et al., 2001[40 ]
Not applicable
Cross-sectional
General
Not informed
10,251
62.6%
6,125
37.4%
(Study conducted on children who were ≥ 10 years old)
0-4 years old, n=9,302 (56.8%)
Not informed
n=332 (2.0%)
Falls, n=10,022 (61.2%)
Koizumi et al., 2000[20 ]
São Paulo, São Paulo, Brazil
Cross-sectional, retrospective
General
Not informed
2784
76.6%
851
23.41%
≤10 years old (20.3%)
Not informed
n=371 (10.2%)
Aggression, n=1,767 (48.6%)
Colli et al., 1997[16 ]
Ribeirão Preto, São Paulo, Brazil
Cross-sectional
General
Mild, n=2,584 (74.5%)
2476
71.4%
992
28.6%
0-10 years old
(about 30% of all men about 10% of all women)
Not informed
n=209 (6%)
Traffic accidents, n=1,241(35.8%)
Gennari et al., 1995[17 ]
São Paulo, Brazil
Prospective
General
Mild, n=47 (47%)
85
85%
15
15%
Closed head injury patients’ mean age: 35.4 years old
Penetrating head injury patients’ mean age: 27.2 years old
Not informed
n=12 (12%)
Traffic accidents, n=40 (40%)
Masini et al., 1994[30 ]
Distrito Federal, Brazil
Retrospective
General
Mild, n=76 (76%)
(Independent 100 people sample)
65
(Independent 100 people sample)
65%
(Independent 100 people sample)
35
(Independent 100 people sample)
35%
(Independent 100 people sample)
1-30 years old, n=72 (72%)
(Independent 100 people sample)
Not informed
n=797 (14.7%)
Traffic accident, n=2391 (44%)
Maset et al., 1993[18 ]
Sao Jose do Rio Preto, São Paulo, Brazil
Cross-sectional
General
Not informed
759
70.0%
325
30.0%
20-29 years old, n=303 (28.0%)
Not informed
Full text was not retrievable
Full text was not retrievable
We also extracted information on the consequences of TBI, patients’ clinical comorbidities,
length of hospital stay, and alcohol consumption ([Table 5 ]). Surprisingly, many studies did not collect any neuroimaging findings, probably
because neuroimaging is often not performed in mild TBI cases.[11 ],[17 ],[18 ],[23 ],[25 ],[28 ],[29 ],[31 ],[34 ],[38 ]. In relation to other clinical findings, TBI was often accompanied by other soft
tissue lesions and limb fractures[16 ],[21 ],[22 ],[29 ],[35 ],[36 ],[37 ]. Alcohol consumption ranged from 11.7 to 42.3%[15 ],[16 ],[23 ],[24 ],[29 ],[36 ].
Table 5
Traumatic brain injury-related consequences, clinical comorbidities, length of hospital
stay, and alcohol intake information in epidemiological studies on traumatic brain
injury.
Reference
Neuroimaging findings
Other clinical comorbidities/findings
Hospital stay length
Alcohol intake
Melo et al., 2019[24 ]
Computerized tomography, n=83 (70.9%) reported no encephalic lesions.
From the remaining patients: (i), n=18 (15.4%) presented frontal lobe lesions; (ii),
n=12 (10.3%) presented parietal lobe lesions; (iii), n=7 (6%) presented temporal lobe
lesions; (iv), n=4 (3.4%) presented occipital lobe lesions.
Not informed
Not informed
19.7% (n=23) of patients displayed intoxication signs, according to their records.
The remaining records did not include any information on patients’ alcoholic statuses.
Marinho et al., 2017[31 ]
Not informed
Not informed
Not informed
Not informed
De Almeida et al., 2016[11 ]
Not informed
Not informed
Mean hospital stay length for: (i) 2008: 5.4 days; (ii) 2009: 5.3 days; (iii) 2010:
5.5 days; (iv) 2011: 5.6 days; (v) 2012: 5.8 days. Overall mean length of hospital
stays: 5.5 days.
Not informed
Vieira et al., 2016[15 ]
Early diffuse axonal injury and intracranial hypertension signs in computerized tomography
are associated with greater mortality
Hypotension, hypertension, hypothermia, hyperthermia, hypoglycemia, hyperglicemia,
bradycardia, tachycardia, and hypoxia.
Not informed
n=33 (42.3%) patients reported alcohol intake prior the trauma event.
Tavares et al., 2014[32 ]
Chronic subdural hematoma, n=63 (32.5%)
Acute extradural hematoma, n=49 (25.3%)
Acute subdural hematoma, n=30(15.5%)
Cerebral edema, n=2 (1.0%)
Firearm projectile, n=7 (3.6%)
Depressed skull fracture, n=38 (19.6%)
Intraparenchymal hematoma, n=5 (2.6%)
Not informed
Not informed
Not informed
De Souza et al., 2013[19 ]
Study conducted on TBI caused by projectile firearms
Frontal lobe lesion, n=49 (27%)
Temporal lobe lesion, n=45 (25%)
Parietal lobe lesion, n=25 (14%)
Occipital lobe lesion, n=31 (17%)
Facial lesion, n=20 (11%)
Multiple lesions, n=11 (6%)
Tangential TBI, n=29 (16%)
Penetrating TBI, n=152 (84%)
Not informed
Not informed
Santos et al., 2013[25 ]
Not informed
Not informed
Not informed
Not informed
Fernandes et al., 2013[33 ]
Study did not specify whether lesions were chronic or acute.
Fractures, n=11,125 (2.5%)
Extradural hematoma, n=20,923 (4.8%)
Subdural hematoma, n=27,447 (6.3%)
Focal lesions, n=31,644 (7.2%)
Diffuse lesions, n=159,241 (36.3%)
Subarachnoid hemorrhage, n=1,856 (0.4%)
Non-specified lesions, n=186,742 (42.5%)
Not informed
Not informed
Not informed
Carvalho Viégas et al., 2013[34 ]
Not informed
Not informed
Not informed
Not informed
Ruy and Rosa, 2011[35 ]
Not informed
Sensory reduction, n=45 (48.5%)
Anisocoria, n=15 (16.3%)
Mental confusion, n=11 (12.1%)
Psychomotor agitation, n=10 (10.9%)
Cardiopulmonary arrest, n=10 (10.9%)
Respiratory failure, n=9 (9.8%)
Seizures, n=6 (6.7%)
ICU clinical complications:
Pneumonia, n=16 (17.3%)
Sepsis, n=2 (2.2%)
Acute renal failure, n=2 (2.2%)
Cerebral hemorrhage, n=36 (38.9%)
Cerebral contusion, n=36 (38.5%)
Cerebral edema, n=23 (24.9%)
Bone fracture of any kind, n=18 (19.6%)
Pneumocephalus, n=12 (12.9%)
Not informed
Not informed
Moura et al., 2011[26 ]
Study did not specify whether lesions were acute or chronic.
Diffuse axonal injury, n=1 (0.99%)
Extradural hematoma, n=20 (19.82%)
Cerebral contusion, n=18 (17.82%)
Subarachnoid hemorrhage, n=10 (9.9%)
Subdural hematoma, n=6 (5.94%)
Most afflicted cranial sites:
Frontal, n=25 (24.75%)
Temporal, n=12 (11.88%)
Temporoparietal, n=12 (11.88%)
Parietal, n=9 (8.91%)
Occipital, n=6 (5.94%)
Parietofrontal, n=6 (5.94%)
Frontotemporal, n=4 (3.96%)
Temporooccipital, n=2 (1.98%)
Basilar skull fracture, n=2 (1.98%)
At admission:
Headache, n=17 (16.83%)
Vomiting, n=16 (15.84%)
Otorrhagia, n=9 (8.91%)
Coma, n=6 (5.94%)
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Ramos et al., 2010[36 ]
General nervous system lesion, n=34 (19.9%)
Bone lesion, n=39 (22.8%)
Vascular lesion, n=55 (32.2%)
Multiple lesions, n=26 (15.2%)
Soft tissues, n=7 (4.1%)
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n=20 (11.7%)
Guerra et al., 2010[21 ]
(Only severe TBI) cases were analyzed)
Diffuse Axonal Injury, n=56 (42.4%)
Swelling, n=74 (56.1%)
Intraparenchymal hemorrhage, n=46 (34.8%)
Subarachnoid hemorrhage, n=41 (31.1%)
Study did not specify whether lesions were acute or chronic:
Subdural hematoma, n=20 (15.2%)
Intraventricular hemorrhage, n=15 (11.4%)
Extradural hematoma, n=14 (10.6%)
Thoracic lesion, n=48 (36.4%)
Skeletal muscle lesion, n=37 (28.0%)
Abdomen, n=21 (15.9%)
Spinal cord, n=6 (4.6%)
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Martins et al., 2009[37 ]
(Only severe TBI cases were analyzed)
Marshall type I injury, n=22 (2.9%)
Marshall type II injury, n=175 (23.4%)
Marshall type III injury, n=172 (23.0%)
Marshall type IV injury, n=58 (7.8%)
Evacuated mass lesion, n=240 (32.1%)
Non-evacuated lesion, n=30 (4.0%)
Brainstem lesion, n=50 (6.7%)
Subarachnoid hemorrhage, n=267 (35.7%)
Face trauma, n=108 (14.4%)
Cervical spine trauma, n=27 (3.6%)
Dorsal-lumbar spine trauma, n=7 (0.9%)
Thoracic trauma, n=141 (18.9%)
Abdominal trauma, n=70 (9.4%)
Limb trauma, n=204 (27.3%)
(Pupil) Isochoric, n=283 (37.8%)
(Pupil) Miotics, n=30 (4.0%)
(Pupil) Anisocorics, n=347 (46.4%)
(Pupil) Mydriatics, n=83 (11.1%)
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Braga et al., 2008[23 ]
(Only TBI cases caused by falling from standing height were analyzed)
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Systemic arterial hypertension, n=9 (11.8%)
Epilepsy, n=6 (7.9%)
Alcoholism, n=4 (5.3%)
Diabetes mellitus, n=3 (3.9)
Heart failure, n=3 (3.9%)
Alzheimer’s disease, n=3 (3.9%)
HIV infection, n=3 (3.9%)
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n=11 (14.5%)
Faria et al., 2008[38 ]
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n=33 (39.3%)
Pereira et al., 2006[27 ]
Altered CT scan, n=75 (31.0%) out of 242
Altered plain radiography of the skull, n=4 (1.7%) out of 239
Altered conscious level, n=85 (18.1%)
Vomiting and nausea, n=97 (20.6%)
Sleepiness, n=51 (10.9%)
Headache, n=40 (8.5%)
Dizziness, n=18 (3.8%)
Seizures, n=11 (2.3%)
Otorrhagia, n=12 (2.6%)
Epistaxis, n=8 (1.7%)
Diplopia, n=2 (0.43%)
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Melo et al., 2006[28 ]
(Study conducted on children and teenagers only)
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Not applicable
Melo et al., 2004[29 ]
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1 lesioned organ, n=117 (66.1%)
2 lesioned organs, n=40 (22.6%)
≥3 lesioned organs, n=20 (11.3%)
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n=27 (4.9%)
Dantas Filho et al., 2004[39 ]
Marshall type I injury, n=15 (7.28%)
Marshall type II injury, n=63 (30.58%)
Marshall type III injury, n=33 (16.02%)
Marshall type IV injury, n=13 (6.31%)
Focal lesion (operated), n=72 (34.95%)
Focal lesion (not operated), n=10 (4.85%)
Hypo-/Hypernatremia and Hypo-/hypercalcemia, n=130 (63.21%)
Polyuria, n=32 (15.53%)
Bronchopneumonia, n=119 (57.77%)
Urinary infection, n=11 (5.34%)
Sepsis, n=10 (4.85%)
Sinusitis, n=6 (2.91%)
Gastrointestinal bleeding, n=3 (1.46%)
Hypoxia, n=81 (39.32%)
Hypotension, n=39 (18.93%)
Both hypoxia and hypotension, n=22 (10.68%)
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Gusmão et al., 2002[22 ]
(Only evaluated fatal patients)
Diffuse axonal injury, n=96 (80.0%)
Intracranial hypertension, n=47 (39.2%)
Skull fracture, n=63 (52.5%)
Hypoxic brain injury: (19.2%)
Limb fractures, n=46 (38.3%)
Thoracic trauma, n=42 (35%)
Abdominal trauma, n=44 (36.7%)
Both thoracic and abdominal trauma, n=32 (26.7%)
Pneumonia, n=10 (8.3%)
Purulent meningitis, n=3 (2.5%)
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Koizumi et al., 2001[40 ]
(Only evaluated children)
Skull fractures, n=1,800 (11%)
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<1 day, n=333 (2.0%)
1 to 3 days, n=12,100 (73.9%)
4 to 7 days, n=2.825 (17.3%)
8 to 29 days, n=1.023 (6.2%)
≥30 days, n=95 (0.6%)
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Koizumi et al., 2000[20 ]
Fracture of skull vault, n=45 (1.2%)
Basilar skull fracture, n=32 (0.9%)
Other skull fractures, n=22 (0.6%)
Multiple fractures of skull/face, n=4 (0.1)
Brain concussion, n=1038 (28.6%)
Cerebral laceration and contusion, n=192 (5.3%)
Hemorrhage, n=509 (14.0%)
Traumatic intracranial lesion of other types, n=1793 (49.3%)
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Most predominant hospital stay duration is of 1 to 7 days hospitalized (n=2,637; 72.5%).
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Colli et al., 1997[16 ]
Plain radiography of the skull: 18.0% (24% of 73%) presented fractures.
CT scan: 4.2% (30% of 14%) presented brain lesions
Scalp lesion: 66.2%
Headache (21.4% of children)
Vomit: 17% (approximately in adult and children)
Headache: 17% (approximately)
Alteration of consciousness (some time after TBI): 24.4%
Alteration of consciousness (immediately afterwards): 87%
Soft tissue lesion: 17.9%
Face lesion: 15.4%*
*Full text was not retrievable. Figure 7 was missing
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17% of adults (approximately)*
Gennari et al., 1995[17 ]
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Penetrating trauma, n=32 (32%)
Blunt trauma, n=68 (68%)
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Masini et al., 1994[30 ]
Chronic subdural hematoma, n=54 (1)
Acute extradural hematoma, n=40 (0.7%)
Acute subdural hematoma, n=40 (0.7%)
General fractures and basilar skull fracture, n=58 (1%)
Cerebral contusion, n=56 (1%)
Firearm projectile induced lesion: 19 (0.4%)
Intracerebral hematoma: 9 (0.2%)
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n=64 (64%) were discharged <24 hours.
n=16 (16%) stayed longer than 7 days.*
*Independent 100 people sample 71.6% patients
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Maset et al., 1993[18 ]
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Average hospital stays: 4.65 days
71.6% patients stayed for a maximum of 4 days.
24.9% patients stayed for 2 days.
1.7% patients stayed for a period greater than 20 days.
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TBI: traumatic brain injury
DISCUSSION
In the present study, we evaluated the sociodemographic and clinical characteristics
of patients with TBI admitted to a public reference trauma center in Minas Gerais,
Brazil. This is the first study to perform such evaluation in the state of Minas Gerais,
specifically at one of the largest reference trauma centers in Brazil. It is worth
highlighting the large number of patients admitted to this center in a short period
of time. The hospital admitted almost 17 patients with TBI every day. Young men were
most commonly affected, and unspecific falls were the most common cause of TBI. Overall,
these findings are consistent with the results of other Brazilian studies, as shown
in our systematic literature review [11 ],[15 ]
-
[40 ].
The higher vulnerability of men can be explained by sociocultural and behavioral factors,
such as higher exposure to urban violence than women[25 ]. A European systematic review found a preponderance of men in 28 studies in which
the male-to-female ratio ranged from 1.2:1.0 to 4.6:1.0[41 ]. Accordingly, men in the United States have higher age-adjusted rates of emergency
department visits and deaths related to TBI[4 ]. In our sample, TBI occurred more frequently in young adults, with mean ages ranging
from 22 to 49 years in different studies[25 ],[41 ],[42 ].
In contrast to most Brazilian reports, the current study found that falls were the
main cause of TBI, but not traffic accidents[29 ],[43 ]. One of the largest epidemiological studies conducted in the Brazilian population
found that falls were the most common TBI mechanism, similar to our findings[33 ]. Falls were also the most common cause of TBI in European countries and in the USA[4 ],[41 ].
Approximately 19% of our sample reported having consumed alcohol prior to the traumatic
event. Our results show that falls, followed by traffic accidents, were the main causes
of TBI in patients under the influence of alcohol. Falls were also the main cause
of TBI in patients under the influence of illicit drugs (mainly marijuana and crack),
but here traffic accident was followed by physical aggression. It is known that the
use of alcohol and illicit drugs favors the occurrence of risky situations[29 ]. In an American study, it was found that both alcohol and illicit drug use were
common before a TBI[43 ]. In Brazil, it is still unclear what role alcohol and other drugs play in TBI[36 ]. Most of the studies included in our review did not evaluate alcohol status of patients,
and those that did had missing data on such information[15 ],[16 ],[23 ],[29 ],[36 ].
Regarding the severity of TBI, as determined by the GCS, the majority of our sample
was diagnosed as mild (87.4%). Mild TBI was also the most common severity level in
the Brazilian studies examined, but studies differed in their sample composition.
For example, Marinho et al. analyzed a group of 18-30-year-old individuals - an age
group more prone to riskier situations and to moderate and severe TBI[29 ],[31 ],[43 ]. Faria et al. grouped severe and moderate TBI together and yet accounted for only
52% of the total cases[38 ].
The clinical meaning of mild TBI should not be underestimated, as it has been associated
with the development of cognitive and behavioral changes[44 ]. According to one scoping review, half of patients with a single episode of mild
TBI develop long-term impairments in several cognitive domains, including executive
functions, learning/memory, attention, processing speed, and language[45 ]. This review included heterogeneous studies using different cognitive batteries
in mild TBI patients at different time points after the traumatic event, which may
explain the high rate of cognitive deficits. For example, significant episodic memory
deficits can already be observed in the acute phase of mild TBI[46 ].
Neuroimaging is an important tool in establishing the prognosis for TBI. Seventy-six
of 436 (17.4%) patients had early tomographic/neuroimaging TBI-related alterations.
It is well known that the more severe the TBI, the more likely the patient is to have
neuroimaging changes[47 ]. Our results confirm that more than half of the patients with moderate or severe
TBI had cranial CT changes. Conversely, about 10% of patients with mild TBI had neuroimaging
changes. Few of the Brazilian studies reviewed included their neuroimaging findings,
as neuroimaging is not considered cost-effective due to the low rate of positive neuroimaging
findings in mild TBI[48 ].
The length of hospital stay was less than 24 hours in 73.6% of the cases, as most
were mild TBI cases. Conversely, a GCS score of 12 or less on admission, as well as
neuroimaging changes and medical comorbidity (i.e., both clinical and psychiatric
conditions), were associated with a longer hospital stay. Similar to our results,
Sorensen et al. found that lower GCS score and psychiatric comorbidity were significantly
associated with delay in hospital discharge in patients with TBI[49 ]. The length of hospital stay in our systematic review varied widely, probably due
to the heterogeneity of the sample and the different protocols for treatment and management
of TBI in different clinical settings.
In the current study, 3.6% of our post-TBI patients died (n=18). Mortality rates should
be interpreted with caution, considering the heterogeneity of epidemiological studies
on TBI. For instance, Fernandes et al. found a mortality rate of 12.0% in a much larger
sample that included over 400,000 records from a much longer time window[33 ]. In Europe, there is also a wide variation in post-trauma mortality rate, ranging
from 3.0/105 inhabitants per year in both Hannover and Münster (Germany) to 18.3/105 per year in Finland and Italy[41 ]. In the USA, about one third of all related deaths are diagnosed with TBI[50 ].
There are limitations to the present study. Some variables (e.g., level of education)
were not available for a significant percentage of patients, reflecting the challenges
of clinical data collection in a busy trauma center, and thus preventing a more thorough
analysis. Medical records also did not include categories of falls. We were only able
to capture serious sequelae during hospitalization, which prevented us from exploring
less severe complications, including cognitive, behavioral or motor symptoms, and
the associated impact on patients’ lives. In addition, the present study was conducted
in a time window of one month within one year - which was one of the main reasons
that led us to conduct a systematic review. From the literature review, we obtained
an accurate snapshot of TBI epidemiology in one of the main trauma centers in one
of the largest metropolitan regions of Brazil. We chose the month of July because
of winter break - a time of year in which people are more exposed to risky situations
(such as car travel) and, consequently, to TBIs.
Future studies with a comprehensive longitudinal evaluation of TBI beyond the acute
phase are warranted. The investigation of regional specificities in TBI profile in
other Brazilian regions and other developing countries could also provide meaningful
clinical and epidemiological information. Only with robust evidence can optimal prevention
and rehabilitation measures be implemented, influencing the outcome of this daunting
problem.
